Storm tracks and cyclogenesis/cyclolysis locations for the past 7 and 30 days.
Tracks are based on an algorithm developed at the Climate Diagnostics Center (CDC) [Serreze (1995), and Serreze et al. (1997)].
Storm tracks are identified by locating grid points in which the sea level pressure (SLP) is less than its surrounding grid points.
The threshold used here is 1 mb.The storms are tracked by analyzing the position of systems between time steps and applying a maximum distance threshold between candidate pairings (800 km).
The intensity of the cyclone is given by the color of the line segment with storms of higher pressure indicated by black and storms with lower pressure indicated in red.
The top three panels show storm tracks and total precipitation (mm), mean anomalous 925 mb wind vectors (m/s), and significant wave heights (m) (from the Ocean Prediction Center) respectively included.
The bottom panel shows cyclogenesis and cyclolysis locations during the period with the smaller dots indicating higher pressure and larger dots lower pressure at the time of development or dissipation.

Latitude-time and time-longitude plots of storm frequency (the number of closed circulations in 10 x 10 degree regions per pentad) for selected cross sections in the northern hemisphere. Each figure below contains four panels corresponding to different cross sections from the western Pacific to the Atlantic.
Each panel contains two figures (one showing the location of the area of interest and the second the storm frequency). A three pentad running mean is applied to the data.

January, February, and March (JFM) storm track frequency binned into 5x5 degree grid boxes composited by ENSO phase. Composites are calculated using the ENSO Intensity Scale (EIS) based on the Oceanic Nino Index (ONI) defined as the three month running mean of SST anomalies for the NINO 3.4 region (Kousky and Higgins, 2004).